German Patent Specification 1,049,380 [Chem. Abstr. 55 (1961)P4532c] refers to a process for preparing .alpha.-substituted pyrrolidines of formula A ##STR1## in which R.degree. denotes a hydrogen atom, alkyl, aryl, aralkyl or a heterocyclic radical;
R' denotes alkyl, aryl, aralkyl, a heterocyclic radical or cyano; and PA1 R" denotes a hydrogen atom or a monovalent organic radical. PA1 each R is, independently, [halo].sub.(2-f) [(alkyl).sub.(2-g) {(-OH).sub.(2-h) [(alkoxy).sub.(2-i) {(acyloxy).sub.(2-j) [(-NH.sub.2).sub.(2-k) {(monosubstituted amino).sub.(2-m) [disubstituted amino).sub.(2-p) {(-NO.sub.2).sub.(2-r) [(phenyl).sub.(2-s) (substituted phenyl).sub.(s-1) ].sub.(r-1) }.sub.(p-1) ].sub.(m-1) }.sub.(k-1) ].sub.(j-1) }.sub.(i-1) ].sub.(h-1) }.sub.(g-1) ].sub.(f-1) ; PA1 each of a, b, c, d, e, f, g, h, i, j, k, m, p, r and s is, independently, a positive whole number of at most 2; and PA1 n is a positive whole number of at most 4; PA1 R.sup.2 denotes halo, alkyl, hydroxyl, alkoxy, acyloxy, optionally-substituted amino, nitro, or optionally-substituted phenyl; and PA1 each of R.sup.3, R.sup.4 and R.sup.5 is, independently, a hydrogen atom, halo, alkyl, hydroxyl, alkoxy, acyloxy, optionally-substituted amino, nitro or optionally-substituted phenyl; PA1 R.sup.1 denotes a hydrogen atom (-H), a straight-chain or branched aliphatic hydrocarbon radical (hydrocarbyl) with from 1 to 5 carbon atoms, cycloalkylalkyl with 1 or 2 carbon atoms in the alkyl radical and from 3 to 5 carbon atoms in the cycloalkyl radical, or optionally mono-substituted phenylalkyl with from 1 to 4 carbon atoms in the alkyl radical; PA1 R.sup.2 denotes halo, hydroxyl (--OH), alkyl with from 1 to 4 carbon atoms, alkoxy with from 1 to 4 carbon atoms, alkanoyloxy with from 2 to 5 carbon atoms, amino (--NH.sub.2), dialkylamino with 1 to 2 carbon atoms per alkyl radical, nitro (--NO.sub.2) or phenyl which is optionally substituted in the p-position; and PA1 each of R.sup.3, R.sup.4 and R.sup.5 is, independently, a hydrogen atom, halo, hydroxyl, alkyl with from 1 to 4 carbon atoms, alkoxy with from 1 to 4 carbon atoms, alkanoyloxy with from 2 to 5 carbon atoms, amino, dialkylamino with 1 or 2 carbon atoms per alkyl radical or nitro, the benzyl nucleus being unsubstituted in at least one of the ortho (2- and 6-) positions; PA1 R.sup.2 denotes halo, hydroxyl, methoxy, amino or nitro; and PA1 R.sup.3 denotes a hydrogen atom, halo, hydroxyl, methoxy, amino or nitro, R.sup.2 and R.sup.3 preferably being in the 2-, 3- and/or 4-position; and PA1 each of R.sup.4 and R.sup.5 is a hydrogen atom; PA1 R.sup.1 denotes a hydrogen atom, methyl, isopropyl or cyclopropylmethyl; PA1 R.sup.2 denotes a 2-, 3- or 4-positioned fluoro, chloro, hydroxy, methoxy or amino substituent; and PA1 R.sup.3 is a hydrogen atom; PA1 R.sup.1 denotes a hydrogen atom (--H), straight-chain or branched aliphatic or alicyclic hydrocarbyl, cycloalkylalkyl or aralkyl; and PA1 each of R.sup.2, R.sup.3, R.sup.4 and R.sup.5 is, independently, a hydrogen atom, halo, alkyl, hydroxyl, alkoxy, acyloxy, optionally-(mono- or di-)substituted amino, nitro or optionally-substituted phenyl; PA1 R.sup.7 represents straight-chain or branched aliphatic or alicyclic hydrocarbyl, cycloalkylalkyl or optionally-substituted aralkyl; PA1 B denotes a hydrogen atom or a precursor of a functional group and PA1 n denotes a whole number from 1 to 4, preferably 1 or 2, and particularly 1; PA1 R.sup.9 denotes straight-chain or branched aliphatic or alicyclic hydrocarbyl, cycloalkylalkyl, optionally-substituted phenyl or optionally-substituted phenylalkyl; PA1 R.sup.10 denotes alkyl with from 1 to 5 carbon atoms. PA1 R.sup.11 represents a hydrogen atom (--H); and PA1 Q represents a --CN group, PA1 R.sup.15 is alternatively cycloalkyl with from 3 to 6 ring carbon atoms or optionally-substituted phenyl; PA1 D and O--R.sup.12 together optionally denote alkylene-dioxy with up to 4, preferably 2, carbon atoms; PA1 Q (in IX) denotes --CO--O--R.sup.10 ; and PA1 each of R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.7 and R.sup.10 has its previously-ascribed meaning; PA1 Q represents --CN or --CO--O--R.sup.10 ; PA1 R.sup.10 has its previously-ascribed meaning; and PA1 L.sup..crclbar. stands for an equivalent of an anion of an organic or inorganic acid.
The compounds obtained according to this process are intended to be used as medicaments; no specific action is assigned to them and .alpha.-phenylpyrrolidine is the sole cited example.
In the course of synthesizing nicotine analogues, J. H. Burckhalter and J. H. Short [J. Org. Chem. 23 (1958) 1281-86] refer to 2-benzylpyrrolidine and to 2-benzyl-1-methylpyrrolidine and draw attention to publications of D. F. Starr et al. [J. Amer. Chem. Soc. 54 (1932) 3971] and cf. R. Lukes [Chem. Listy 27 (1933) 392, 409; Chem. Abstr. 29 (1935) 1720]. 2-Benzyl-1-methylpyrrolidine was obtained in a low yield by Fery and van Hove [Bull. Soc. chim. Belg. 69 (1960) 63-78; Chem. Abstr. 55 (1961) 4475d] through rearrangement of 1-methyl-1-benzylpyrrolidinium iodide. Within the scope of their work on rearranging .alpha.-aminoketones during a Clemmensen reduction, N. J. Leonard et al. [J. Amer. Chem. Soc. 75 (1953) 3727-30] describe preparing 1-ethyl-2-benzylpyrrolidine without stating any pharmacological activity for the latter substance. 2-benzylpyrrolidine showed no activity with regard to hypertension caused by adrenalin; 2-benzyl-1-methylpyrrolidine caused only a partial reduction of hypertension induced by adrenalin. Any anti-hypertensive utility of either of the last two noted compounds is highly doubtful and such utility, if it does exist, is expected to be severely limited in extent. German Offenlegungsschrift (Published Specification) 25 48 053 [Derwent, Pharmdoc Basic Number 36351X/20] refers to saturated .alpha.-substituted benzyl-1-benzhydrylazaheterocyclic compounds, in particular .alpha.-substituted benzyl-1-benzhydrylazetidines for treating obesity.